In recent years, carbon dioxide (hereinafter referred to as CO2) is pointed out as one of causes of the global warming phenomenon. Therefore, a method of bringing a combustion gas of a boiler into contact with an absorbent and eliminating and recovering CO2 in the combustion gas, and a method of storing the recovered CO2 without discharging the CO2 to the atmospheric have been extensively studied for, for example, power generation facilities, such as a thermoelectric power plant that uses a large quantity of fossil fuels.
CO2 recovery devices include, as basic constituent elements, an absorption tower that causes CO2 in gas to be absorbed into an absorbent, and a regeneration tower that separates CO2 from the absorbent. In order to properly operate the CO2 recovery devices, several proposals as shown below have been made up to now.
The volume of exhaust gas required for attaining an objective is determined from a target CO2 recovery volume and CO2 concentration in the exhaust gas, and the exhaust gas is supplied to a CO2 recovery device (for example, PTL 1).
The volume of exhaust gas from an exhaust gas source (a boiler or a gas turbine installed upstream of a CO2 recovery device) and CO2 concentration in the exhaust gas are measured, and operation parameters required for achieving a target CO2 recovery rate are determined (for example, PTL 2).
The flow rate of the gas discharged to the atmosphere through a chimney without being treated by a CO2 recovery device, and the composition of this gas are measured using the gas from an exhaust gas source, and the volume of exhaust gas to be supplied to the CO2 recovery device is determined so as not to produce a stream that flows into the chimney from the atmosphere (for example, PTL 3).